Performance Prediction of a Solar District Cooling System in Riyadh, Saudi T Arabia – a Case Study ⁎ G

Total Page:16

File Type:pdf, Size:1020Kb

Performance Prediction of a Solar District Cooling System in Riyadh, Saudi T Arabia – a Case Study ⁎ G Energy Conversion and Management 166 (2018) 372–384 Contents lists available at ScienceDirect Energy Conversion and Management journal homepage: www.elsevier.com/locate/enconman Performance prediction of a solar district cooling system in Riyadh, Saudi T Arabia – A case study ⁎ G. Franchini , G. Brumana, A. Perdichizzi Department of Engineering and Applied Sciences, University of Bergamo, 5 Marconi Street, Dalmine 24044, Italy ARTICLE INFO ABSTRACT Keywords: The present paper aims to evaluate the performance of a solar district cooling system in typical Middle East Solar cooling climate conditions. A centralized cooling station is supposed to distribute chilled water for a residential com- District cooling pound through a piping network. Two different solar cooling technologies are compared: two-stage lithium- Parabolic trough bromide absorption chiller (2sABS) driven by Parabolic Trough Collectors (PTCs) vs. single-stage lithium-bro- Absorption chiller mide absorption chiller (1sABS) fed by Evacuated Tube Collectors (ETCs). A computer code has been developed Thermal storage in Trnsys® (the transient simulation software developed by the University of Wisconsin) to simulate on hourly basis the annual operation of the solar cooling system, including building thermal load calculation, thermal losses in pipes and control strategy of the energy storage. A solar fraction of 70% was considered to size the solar field aperture area and the chiller capacity, within a multi-variable optimization process. An auxiliary com- pression chiller is supposed to cover the peak loads and to be used as backup unit. The two different solar cooling plants exhibit strongly different performance. For each plant configuration, the model determined the optimal size of every component leading to the primary cost minimization. The solar district cooling configuration based on 2sABS and PTCs shows higher performance at Riyadh (KSA) climate conditions and the overall cost is 30% lower than the one of the single-stage absorption chiller plant. 1. Introduction different integration scenarios including cogeneration, trigeneration and district heating/cooling. District energy systems have attracted great interest over the last A further milestone in the development of district energy systems decades thanks to the undeniable environmental and economic benefits has been derived from the integration of energy storages in district and the high level of efficiency and reliability. Boran et al. [1] ex- heating [7–9], as well as in district cooling. The storage can be diurnal amined district heating systems and concluded that they are responsible or seasonal [10]. Powell et al. [11] presented a new methodology to for 33% equivalent CO2 savings compared to conventional gas boilers optimize the operation of the cooling unit coupled with tanks. Gang used for heating, and electricity from the grid for electrical demand. et al. [12] investigated a district cooling system with thermal storage Casisi et al. [2] investigated a distributed cogeneration system with a integrated into a trigeneration plant serving a residential compound in district heating network, applied to a real city center: they demon- a subtropical area. The results of their work show that an appropriate strated that both microturbines and ICEs designed for CHP applications design can lead to economic, environmental and energy savings. are competitive with respect to conventional energy supply. Many pa- The integration of renewable sources into district energy systems is pers focus on improving the system at the network level. The network a way to increase the environmental sustainability, in spite of the im- operation is deeply analyzed in [3,4]: the authors developed a detailed pact on the initial investment [8]. Liew et al. [13] analyzed several numerical model based on a quasi-static approach for the hydraulic options to integrate different energy systems including renewable in behavior and a transient model for the thermal one. Despite most of the different types of building complexes. The exploitation of geothermal existing district energy systems are for heating purpose [5], in recent energy for district heating systems has been deeply investigated [14]. years the development of district cooling systems has grown up due to Heat can be extracted from the ground directly or with the use of heat the increase of the global energy demand for air conditioning. The pumps [15]. growth of district cooling systems is linked to the development and Integrating solar energy into district heating systems is a challenge marketing of absorption chillers: Ameri and Besharati [6] evaluated of recent years [16]. The main issues are the variability of the source, ⁎ Corresponding author. E-mail address: [email protected] (G. Franchini). https://doi.org/10.1016/j.enconman.2018.04.048 Received 22 January 2018; Received in revised form 11 April 2018; Accepted 12 April 2018 Available online 03 May 2018 0196-8904/ © 2018 Elsevier Ltd. All rights reserved. G. Franchini et al. Energy Conversion and Management 166 (2018) 372–384 Nomenclature Ecoll heat collected by the solar field (MWh) Erad radiant solar energy (MWh) 1sABS single-stage absorption chiller ETC evacuated tube collector 2sABS two-stage absorption chiller G-value,w window solar factor 2 a0 collector optical efficiency GHI global horizontal irradiance (W/m ) 2 a1 collector 1st order loss coefficient (W/m /K) HX heat exchanger 2 2 a2 collector 2nd order loss coefficient (W/m /K ) ICE internal combustion engine 2 Acoll aperture area of the solar field (m ) PTC parabolic trough collector AHU air handling unit Q̇abs cooling power of absorption chiller (1s or 2s) (kW) 2 ̇ BTI beam tilted irradiance (W/m ) Q aux cooling power of auxiliary chiller (kW) ̇ fi Cap capacity of the absorption chiller (kW) Q coll thermal power collected by solar eld (kW) Abs ̇ CC compression chiller Q rad radiant power (kW) CHP combined heat and power SF solar fraction fl CHW chilled water T mean temperature between inlet and outlet ow rates (°C) Tamb ambient temperature (°C) CostAbs unit cost of the absorption chiller ($/kW) 2 Ttank.bottom temperature at tank bottom (°C) Costcoll unit cost of solar collectors ($/m ) 3 Ttank.top temperature at tank top (°C) Costtank unit cost of the tank ($/m ) 2 CR concentration ratio Uroof roof U-value (W/m /K) 2 CW cooling water U-value,w window U-value (W/m /K) 2 DNI direct normal irradiance (W/m2) Uwall wall U-value (W/m /K) 3 E cooling energy produced by the absorption (1s or 2s) Voltank tank volume (m ) abs η ffi – chiller (MWh) e ciency ( ) θ incidence angle (°) Eaux cooling energy produced by the auxiliary chiller (MWh) thus requiring a thermal energy storage system, and the critical over- powered by parabolic trough solar collectors, with operating tempera- heating during the off-heating season. To avoid these problems keeping tures varying in the range 20–160 °C. high the solar contribution, it is essential to design powerful predictive In the open literature, the potential benefits deriving from the in- models of load management and storage tanks: Daniel Trier [17] has tegration of PTCs and 2sABS are substantially unexplored. Starting from investigated district heating systems with a solar fraction of more than previous researches on the modeling and the analysis of buildings and 70%. Often, the solar thermal systems operating in a district heating solar cooling plants [39,40], this work presents a solar district cooling network are coupled with biomass boilers [18]. Therefore, research is model capable of predicting with accuracy the global performance of focused on improving the efficiency of the production plant [19] and the system and the behavior of each single component in design and off- the network [20,21], by means of detailed computer models and si- design operating conditions. mulation tools [22] and genetic optimization algorithms [23]. Subse- Moreover, the paper deals with the system optimization. It is well quently, the integration of the solar contribution is also extended to the known that an optimal plant configuration is crucial for solar driven cooling systems as a direct result of the development of solar cooling technologies, in order to maximize the overall efficiency and to mini- technologies for individual buildings [24]. mize the investment costs, as well documented by Hang et al. [41]. Only a few articles deal with the integration of solar energy in Among the available optimization methods, the integration of dynamic district cooling systems [25–28]. Marugàn-Cruz et al. analyzed the in- simulations based on the Trnsys software and the Hooke and Jeeves tegration of a high temperature solar technology (solar tower) into a optimization algorithm [42] was proved to be a remarkable solution. A district cooling system to enhance the energy surplus in the warm deep explanation of the Hooke and Jeeves direct search algorithm and season [29]. The integration of concentrated solar power plants with its benefits is reported by Kirgat and Surde in [43]. cooling energy production is investigated also in [30], where the au- The paper firstly introduces the Trnsys models developed for re- thors demonstrated that the combined power and cooling production producing the cooling load of a residential compound, the district for plants operating in island-mode can improve the overall global ef- cooling network and the cooling plant based on two different absorp- ficiency. The abovementioned systems are basically large-scale solar tion chillers: double-stage unit powered by a PTC field and single-stage power plants with heat recovery for cooling production via absorption machine driven by ETCs. A set of dynamic simulations have been per- or adsorption chillers. For smaller sizes, typically the solar field is di- formed using the GenOpt optimization tool in order to maximize the rectly connected to the thermally driven chiller [31–33]. The most thermo-economic performance of the systems. common configuration is based on ETCs coupled with a single-stage LiBr absorption chiller [34,35]: evacuated tube collectors with selective 2.
Recommended publications
  • Economic and Environmental Analysis of Investing in Solar Water Heating Systems
    sustainability Article Economic and Environmental Analysis of Investing in Solar Water Heating Systems Alexandru ¸Serban 1, Nicoleta B˘arbu¸t˘a-Mi¸su 2, Nicoleta Ciucescu 3, Simona Paraschiv 4 and Spiru Paraschiv 4,* 1 Faculty of Civil Engineering, Transilvania University of Brasov, 500152 Brasov, Romania; [email protected] 2 Faculty of Economics and Business Administration, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania; [email protected] 3 Faculty of Economics, Vasile Alecsandri University of Bacau, 157 Marasesti Street, 600115 Bacau, Romania; [email protected] 4 Faculty of Engineering, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-721-320-403 Academic Editor: Francesco Asdrubali Received: 26 August 2016; Accepted: 2 December 2016; Published: 8 December 2016 Abstract: Solar water heating (SWH) systems can provide a significant part of the heat energy that is required in the residential sector. The use of SWH systems is motivated by the desire to reduce energy consumption and especially to reduce a major source of greenhouse gas (GHG) emissions. The purposes of the present paper consist in: assessing the solar potential; analysing the possibility of using solar energy to heat water for residential applications in Romania; investigating the economic potential of SWH systems; and their contribution to saving energy and reducing CO2 emissions. The results showed that if solar systems are used, the annual energy savings amount to approximately 71%, and the reduction of GHG emissions into the atmosphere are of 18.5 tonnes of CO2 over the lifespan of the system, with a discounted payback period of 6.8–8.6 years, in accordance with the savings achieved depending on system characteristics, the solar radiation available, ambient air temperature and on heating load characteristics.
    [Show full text]
  • A Comprehensive Review of Thermal Energy Storage
    sustainability Review A Comprehensive Review of Thermal Energy Storage Ioan Sarbu * ID and Calin Sebarchievici Department of Building Services Engineering, Polytechnic University of Timisoara, Piata Victoriei, No. 2A, 300006 Timisoara, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-256-403-991; Fax: +40-256-403-987 Received: 7 December 2017; Accepted: 10 January 2018; Published: 14 January 2018 Abstract: Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground, and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included. Keywords: storage system; phase-change materials; chemical storage; cold storage; performance 1. Introduction Recent projections predict that the primary energy consumption will rise by 48% in 2040 [1]. On the other hand, the depletion of fossil resources in addition to their negative impact on the environment has accelerated the shift toward sustainable energy sources.
    [Show full text]
  • Fifth-Generation District Heating and Cooling Substations: Demand Response with Artificial Neural Network-Based Model Predictive Control
    energies Article Fifth-Generation District Heating and Cooling Substations: Demand Response with Artificial Neural Network-Based Model Predictive Control Simone Buffa 1,*, Anton Soppelsa 1 , Mauro Pipiciello 1, Gregor Henze 2,3,4 and Roberto Fedrizzi 1 1 Eurac Research, Institute for Renewable Energy, Viale Druso 1, 39100 Bolzano, Italy; [email protected] (A.S.); [email protected] (M.P.); [email protected] (R.F.) 2 Department of Civil, Environmental and Architectural Engineering, University of Colorado Boulder, Boulder, CO 80309-0428, USA; [email protected] 3 National Renewable Energy Laboratory, Golden, CO 80401, USA 4 Renewable and Sustainable Energy Institute, Boulder, CO 80309, USA * Correspondence: simone.buff[email protected]; Tel.: +39-0471-055636 Received: 16 July 2020; Accepted: 11 August 2020; Published: 21 August 2020 Abstract: District heating and cooling (DHC) is considered one of the most sustainable technologies to meet the heating and cooling demands of buildings in urban areas. The fifth-generation district heating and cooling (5GDHC) concept, often referred to as ambient loops, is a novel solution emerging in Europe and has become a widely discussed topic in current energy system research. 5GDHC systems operate at a temperature close to the ground and include electrically driven heat pumps and associated thermal energy storage in a building-sited energy transfer station (ETS) to satisfy user comfort. This work presents new strategies for improving the operation of these energy transfer stations by means of a model predictive control (MPC) method based on recurrent artificial neural networks. The results show that, under simple time-of-use utility rates, the advanced controller outperforms a rule-based controller for smart charging of the domestic hot water (DHW) thermal energy storage under specific boundary conditions.
    [Show full text]
  • Solar Community Energy and Storage Systems for Cold Climates
    SOLAR COMMUNITY ENERGY AND STORAGE SYSTEMS FOR COLD CLIMATES by Farzin Masoumi Rad Bachelor of Applied Science (Mechanical Engineering), Shiraz University, Iran, 1986 Master of Applied Science (Mechanical Engineering), Ryerson University, Toronto, Canada, 2009 A dissertation presented to Ryerson University in partial fulfilment of the requirements for degree of Doctor of Philosophy in the program of Mechanical and Industrial Engineering Toronto, Ontario, Canada, 2016 © Farzin M. Rad 2016 Author’s Declaration I hereby declare that I am the sole author of this dissertation. This is a true copy of the dissertation, including any required final revisions, as accepted by my examiners. I authorize Ryerson University to lend this thesis to other institutions or individuals for the purpose of scholarly research. I further authorize Ryerson University to reproduce this thesis by photocopying or by other means, at the request of other institutions or individuals for the purpose of scholarly research. I understand that my dissertation may be made electronically available to the public. ii SOLAR COMMUNITY ENERGY AND STORAGE SYSTEMS FOR COLD CLIMATES Farzin Masoumi Rad Doctor of Philosophy Department of Mechanical and Industrial Engineering Ryerson University, Toronto, Ontario, Canada, 2016 Abstract For a hypothetical solar community located in Toronto, Ontario, the viability of two separate combined heating and cooling systems were investigated. Four TRNSYS integrated models were developed for different cases. First, an existing heating only solar community was modeled and compared with published performance data as the base case with suggested improvements. The base case community was then used to develop a hypothetical solar community, located in Toronto, requiring both heating and cooling.
    [Show full text]
  • Solar Combisystems
    Method and comparison of advanced storage concepts A Report of IEA Solar Heating and Cooling programme - Task 32 “Advanced storage concepts for solar and low energy buildings” Report A4 of Subtask A December 2007 Jean-Christophe Hadorn Thomas Letz Michel Haller Method and comparison of advanced storage concepts Jean-Christophe Hadorn, BASE Consultants SA, Geneva, Switzerland Thomas Letz INES Education, Le Bourget du Lac, France Contribution on method: Michel Haller Institute of Thermal Engineering Div. Solar Energy and Thermal Building Simulation Graz University of Technology Inffeldgasse 25 B, A-8010 Graz A technical report of Subtask A BASE CONSULTANTS SA 8 rue du Nant CP 6268 CH - 1211 Genève INES - Education Parc Technologique de Savoie Technolac 50 avenue du Léman BP 258 F - 73 375 LE BOURGET DU LAC Cedex 3 Executive Summary This report presents the criteria that Task 32 has used to evaluate and compare several storage concepts part of a solar combisystem and a comparison of storage solutions in a system. Criteria have been selected based on relevance and simplicity. When values can not be assessed for storage techniques to new to be fully developped, we used more qualitative data. Comparing systems is always a very hard task. Boundary conditions and all paramaters must be comparable. This is very difficult to achieve when 9 analysts work around the world on similar systems but with different storage units. This report is an attempt of a comparison. Main generic results that we can draw with some confidency from the inter comparison of systems are: - The drain back principle increases thermal performances because it does not use of a heat exchanger in the solar loop and increases therefore the efficiency of the solar collector.
    [Show full text]
  • District Cooling Systems
    DEPARTMENT OF TECHNOLOGY AND BUILT ENVIRONMENT TECHNOLOGICAL AND ECONOMIC EVALUATION OF DISTRICT COOLING WITH ABSORPTION COOLING SYSTEMS IN GÄVLE (SWEDEN) Elixabet Sarasketa Zabala June 2009 Master’s Thesis in Energy Systems uuir Master Programme in Energy Systems Examiner: Ulf Larsson Supervisor: Åke Björnwall Preface This investigation, as final Thesis Project of Master in Energy Systems (University of Gävle), was started to carry out in February, in collaboration with the company Gävle Energi AB. Many people have been involved answering my questions, providing me with information and so forth; some of those are mentioned below. First of all, I would like to thank Åke Björnwall, my supervisor at Gävle Energi AB, very much for his attention, help and support. His knowledge, comments, guidance and advices have been essential for the development of my work. Needless to say that I have learnt a lot from him. Secondly, I would like to thank the rest of workers at Gävle Energi AB, who have done everything they can to help me, in addition to make pleasant my stay in the company. I would also like to thank Ulf Larsson at the University of Gävle for his help. Furthermore, I am very grateful for all information I have received from other companies. Finally, I do not forget the invaluable support of my mother, Rosa, during all my studies. No one mentioned, no one forgotten. Gävle, June 2009 Elixabet Sarasketa Zabala Abstract Gävle Energi AB is a company which produces electricity as well as heat that is delivered through a district heating network in the municipality of Gävle.
    [Show full text]
  • RESET CHAPTER 2: Development and Assessment of Methodologies to Improve Local Microclimate with the Use of RES Techniques
    CONTENTS RESSET - Chapter 1: Collection and documentation of the input data and evaluation tools required to carry out the study................................................................................................................................ 4 1. Development and assessment of methodologies to improve local microclimate with the use of RES techniques............................................................................................................................................. 4 1.1. Introduction.................................................................................................................................... 4 1.2. Energy Balance of Settlements ...................................................................................................... 4 1.3. Microclimate in Settlements .......................................................................................................... 5 1.4. Use of Passive Cooling Techniques applied to Outdoor Spaces ................................................... 6 2. Passive solar heating and cooling and advanced glazing materials...................................................... 8 2.1. Introduction.................................................................................................................................... 8 2.2. Building-integrated PV .................................................................................................................. 8 2.3. Passive solar systems ....................................................................................................................
    [Show full text]
  • District Energy Enters the 21St Century
    TECHNICAL FEATURE This article was published in ASHRAE Journal, July 2015. Copyright 2015 ASHRAE. Posted at www.www.burnsmcd.com .org. This article may not be copied and/or distributed electronically or in paper form without permission of ASHRAE. For more information about ASHRAE Journal, visit www.ashrae.org. District Energy Enters The 21st Century BY STEVE TREDINNICK, P.E., MEMBER ASHRAE; DAVID WADE, P.E., LIFE MEMBER ASHRAE; GARY PHETTEPLACE, PH.D., P.E., MEMBER ASHRAE The concept of district energy is undergoing a resurgence in some parts of the United States and the world. Its roots in the U.S. date back to the 19th century and through the years many technological advancements and synergies have developed that help district energy efficiency. This article explores district energy and how ASHRAE has supported the industry over the years. District Energy’s Roots along with systems serving groups of institutional build- District energy systems supply heating and cooling ings, were initiated and prospered in the early decades to groups of buildings in the form of steam, hot water of the 1900s and by 1949 there were over 300 commercial or chilled water using a network of piping from one or systems in operation throughout the United States. Of more central energy plants. The concept has been used course, systems in the major cities of Europe also gained in the United States for more than 140 years with the favor in Paris, Copenhagen and Brussels. In many cases first recognized commercial district energy operation district steam systems were designed to accept waste originating in Lockport, N.Y.
    [Show full text]
  • Integration of Micro-Cogeneration Units and Electric Storages Into a Micro-Scale Residential Solar District Heating System Operating with a Seasonal Thermal Storage
    energies Article Integration of Micro-Cogeneration Units and Electric Storages into a Micro-Scale Residential Solar District Heating System Operating with a Seasonal Thermal Storage Antonio Rosato * , Antonio Ciervo, Giovanni Ciampi , Michelangelo Scorpio and Sergio Sibilio Department of Architecture and Industrial Design, University of Campania Luigi Vanvitelli, 81031 Aversa, Italy; [email protected] (A.C.); [email protected] (G.C.); [email protected] (M.S.); [email protected] (S.S.) * Correspondence: [email protected]; Tel.: +39-081-501-0845 Received: 31 July 2020; Accepted: 9 October 2020; Published: 19 October 2020 Abstract: A micro-scale district heating network based on the operation of solar thermal collectors coupled to a long-term borehole thermal storage is modeled, simulated and investigated over a period of five years. The plant is devoted to covering the domestic hot water and space heating demands of a district composed of six typical residential buildings located in Naples (southern Italy). Three alternative natural gas-fueled back-up auxiliary systems (condensing boiler and two different technologies of micro-cogeneration) aiming at balancing the solar energy intermittency are investigated. The utilization of electric storages in combination with the cogeneration systems is also considered with the aim of improving the self-consumption of cogenerated electric energy; heat recovery from the distribution circuit is also evaluated to pre-heat the mains water for domestic hot water production. The performances of the proposed plant schemes are contrasted with those of a typical Italian decentralized heating plant (based on the utilization of natural gas-fueled non-condensing boilers).
    [Show full text]
  • Thermal Storage Technology Assessment an Introductory Assessment of Thermal Storage in Residential Cold Climate Construction
    Thermal Storage Technology Assessment An introductory assessment of thermal storage in residential cold climate construction February 2013 by Vanessa Stevens Colin Craven Bruno Grunau With funding from the Alaska Housing Finance Cor- poration & the Alaska Department of Commerce, Community, and Economic Development Acknowledgements The authors would like to acknowledge the many people who participated in interviews for this report, sharing their knowledge and expertise on the topic of thermal storage. Several of the systems built by these individuals appear in Appendix B. Also, thanks to the Alaska Department of Commerce, Community, and Economic Development and the Alaska Housing Finance Corporation for providing funding for this project. 3 Thermal Storage Technolog y Assessment www.cchrc.org Contents Acronyms ............................................................................................................................................................ 5 Introduction ........................................................................................................................................................ 6 1. Thermal Storage Fundamentals........................................................................................................................ 7 1.1 Definition ................................................................................................................................................... 7 1.2 Uses of thermal storage ............................................................................................................................
    [Show full text]
  • Production of District Heating, District Cooling, Electricity and Biogas Our
    Our dream – a city free from fossil fuels Application – First Global District Energy Climate Awards Production of district heating, district cooling, electricity and biogas Borås Energi och Miljö AB, Sweden Borås Energi och Miljö AB, is a municipally owned company and part of Borås Stadshus AB. Contact: Jonas Holmberg – Head of Marketing, +46 33 35 72 20, [email protected] www.borasenergimiljo.se Part of Borås Stadshus AB Borås is Sweden’s 13th largest municipally. Around 64,000 people live in Borås City, and over 100,000 The accumulator tank. throughout the municipality. Borås Energi och Miljö AB (BEM) is a municipally owned company that handles refuse and the production of district heating, cooling and electricity in the municipality of Borås. The company has a vision of a city free from fossil fuels. BEM runs a number of facilities and services, all of which contribute to the reduction of greenhouse gas emissions in one way or another. The term “emissions” used in thes document usally refers to greenhouse gases. First off, please watch our company movie for a quick tour of our company. Click here to watch the movie. We harness all energy streams Whenever they sort their household waste, travel on Today Borås City is a pioneer when it comes to working biogas buses, relax at home with comfortable district in harmony with the biological cycle, and we look on heating or spend time at an office with pleasant district combustible household refuse as a valuable energy cooling, the inhabitants of Borås play an important role resource – energy that would otherwise be wasted.
    [Show full text]
  • Dynamic Performance of a Solar Hybrid Heating Network Integrated with a Micro
    ________________________________________________________________________________________________ Dynamic Performance of a Solar Hybrid Heating Network Integrated with a Micro- Cogeneration Unit Serving a Small-Scale Residential District including Electric Vehicles Antonio Rosato, Antonio Ciervo, Giovanni Ciampi, Michelangelo Scorpio, Francesco Guarino, Sergio Sibilio University of Campania Luigi Vanvitelli, Department of Architecture and Industrial Design, Aversa, Italy Abstract (Angrisani et al., 2014). The micro-cogeneration devices applied in residential units generally operate under a heat- A solar hybrid district heating network integrated with a load following control strategy in response to variations seasonal borehole thermal energy storage is modelled, in heat demand (Sibilio and Rosato, 2015); in this case, a simulated and analyzed over a 5-year period. The system large fraction of the cogenerated electricity is usually is devoted to satisfying the thermal demand of a small- produced at times when the electric demand of the scale district consisting of 6 typical Italian single-family building is lower than MCHP electric output due to the houses in Naples (south of Italy); the charging of 6 plug- usual mismatch between electric and thermal demands in electric vehicles is also considered. The performance of (Ribberink and Entchev, 2014), requiring substantial the proposed plant is investigated by considering two amounts of electricity to be exported to the grid with low alternative natural gas-fueled back-up systems. The revenues. EVs consume considerable amounts of energy, environmental and economic performance of the electricity; they are mostly driven during the day and proposed plant are analyzed and compared with those charged at home during the night, so that the recharging associated to a conventional heating system in order to of EVs could be a way to increase the own use of assess the potential benefits.
    [Show full text]